1. Field of the Invention
The present invention relates to paraffin removal. More particularly, the present invention relates to apparatus for and methods of removing paraffin accumulations from oil wells.
2. General Background of the Invention
Some petroleum deposits contain paraffin therein. At the elevated temperatures underground, this paraffin is a liquid and flows easily. When, however, the petroleum travels through a well bore toward the surface, the petroleum and paraffin cool off. At some point below the surface, the temperature is usually low enough that the paraffin solidifies in the well bore. The solidified paraffin slows down production of oil from the well bore, and thus it is periodically cleaned from the well bore.
A common way to clean paraffin deposits is to drop a scraper on a wireline into the well bore below the paraffin deposit, and then pull the scraper upward, scraping off paraffin as the scraper approaches the surface. The paraffin is usually then sent down the production flow line, moving the paraffin problem from downhole to the production flow line. The production flow line is then treated with hot oil to clean the paraffin out of it.
Flowlines and wellbores are also sometimes treated with chemicals to help combat the paraffin problem. These chemicals are often hazardous.